Alaska is entering new era of wildfires

Alaska, the great northern frontier of America, is being reshaped by climate change. While rising temperatures are altering its character and landscape, they are also bringing the ravages of wildfires.

In the past 60 years, Alaska has warmed more than twice as fast as the rest of the country, with average temperatures up by nearly 3°F. By 2050, temperatures are projected to climb an additional 2-4 degrees, with the Arctic region seeing the most dramatic increases. These rising temperatures are expected to increase wildfire risks in Alaska, just as they have in the rest of the western US.

Wildfires have been on the rise across the western US since the 1970s, at the same time that spring and summer temperatures have increased dramatically, and average spring snowpack has declined substantially.

Fires in Alaska don’t often make news in the lower 48, but they threaten vast expanses of forest, parkland, and tundra that store immense quantities of carbon. The state’s growing number of large wildfires have the potential to damage these ecosystems, and the people and wildlife that depend on them, while releasing a significant amount of carbon into the atmosphere, further contributing to global warming. Wildfire emissions over these vast areas also threaten air quality in Alaska and beyond.

Our analysis of 65 years of Alaska wildfire data show:

The number of large wildfires (larger than 1,000 acres) suddenly increased in the 1990s, and the 2000s saw nearly twice as many large wildfires as the 1950s and 60s.

In the Arctic region, the number of large wildfires increased nearly tenfold in the 2000s compared to the 1950s and 60s. Only three years in the 1950s and 1960s saw large wildfires; there have been 33 large wildfires in the Arctic since 2000.

The area burned in large wildfires each year is increasing. In just two years, 2004 and 2005, wildfires burned a larger area than in the 15 years from 1950-1964 combined. In particular, there has been a dramatic increase in wildfires larger than 10,000 acres but smaller than 50,000 acres.

Alaska’s wildfire season is about 40 percent longer now than it was in the 1950s. The first wildfires start earlier in the year, and the last wildfires are burning longer into the fall. Overall, the wildfire season has increased more than 35 days and is now more than three months long, running from May through early August.

Rising temperatures across Alaska have been concurrent with the rise in the number and size of Alaskan wildfires. Years with the hottest May to July temperatures also tend to be years with the most fires, and the greatest area burned.

According to the National Climate Assessment, the amount of area burned in Alaskan wildfires is projected to double by 2050 and triple by 2100 under continued emissions and further warming.